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Short-range spectroscopic ruler based on a single-molecule optical switch

Mark Bates·Timothy R. Blosser·Xiaowei Zhuang
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Abstract

We demonstrate a novel all-optical switch consisting of two molecules: a primary fluorophore that can be switched between a fluorescent and a dark state by light of different wavelengths, and a secondary chromophore that facilitates switching. The interaction between the two molecules exhibits a distance dependence much steeper than that of Forster resonance energy transfer. This enables the switch to act as a ruler with the capability to probe distances difficult to access by other spectroscopic methods, thus presenting a new tool for the study of biomolecules at the single-molecule level.

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Mark Bates, Timothy R. Blosser, Xiaowei Zhuang. 2005-02-14. Short-range spectroscopic ruler based on a single-molecule optical switch. https://doi.org/10.1103/physrevlett.94.108101

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